Reinforced thermoplastic patient restraints for radiation therapy

Abstract

A patient restraint member is provided for medical procedures, such as radiation therapy. The restraint member is formed from a sheet of thermoplastic material that can be softened upon heating so as to be formable into a shape corresponding to a patient's body part to be restricted and setting upon cooling to retain the shape. The sheet includes spaced apart groups of perforations which minimize shrinkage during the formation process. The sheet also includes solid bands extending between the groups of perforation to provide rigidity and strength to the formed sheet.

Description

BACKGROUND OF THE INVENTION[0001]Thermoplastic sheets are well known for use in the field of radiation therapy treatment, including Intensity Modulated Radiation Therapy (IMRT). Typically, such thermoplastic sheets are heated and then formed to a shape corresponding to the body part to be restrained, such as a mask for restraining a patient's head. The sheet is mounted on a frame which can be secured to a treatment table to facilitate proper positioning of the patient on the table for radiation treatment.[0002]The prior art thermoplastic sheets are solid sheets or perforated sheets. Solid thermoplastic sheets require much higher forces to form, retain much more heat and tend to have excess shrinkage when formed to the body shape, all of which leads to patient discomfort. The perforations serve to reduce the force necessary to form, minimize the heat transferred to the patient, and minimize shrinkage of the thermoplastic material. When the sheet is formed into a facemask, the holes p...

AI Technical Summary

Benefits of technology

[0009]The improved thermoplastic sheet of the present invention is intended for use as a patient restraint member in medical procedures such as radiation therapy treatment, including IMRT. The sheet may take various forms and shapes to restrain various body parts, including the head, neck, breasts, and hips / pelvic area. The sheet includes a plurality of groups of perforations to increase patient comfort with non-perforated bands extending between the groups of perforation to provide enhanced rigidity. The perforations also minimize shrinkage of the sheet when it is heated, formed, and cooled into a set shape corresponding to the body part to be restrained. The perimeter edge of the sheet is free from perforations. The solid bands extend inwardly from the perimeter edge of the sheet The bands may extend completely or partially across the sheet The solid bands are placed in strategic areas to provide increased rigidity while the perforations minimize shrinkage. The perforations may be punched or formed during injection molding.

Problems solved by technology

Solid thermoplastic sheets require much higher forces to form, retain much more heat and tend to have excess shrinkage when formed to the body shape, all of which leads to patient discomfort.

However, totally perforated sheets do not offer the necessary rigidity which is present in a solid or non-perforated sheet.

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